Polished rod clamp



April 18,1944. K. N. MILLS POLISHED ROD CLAMP Filed Jan. 8. 1942 -s snets-sheet 1 April 18, 1944- -K. N. MILLS POLISHED ROD CLAMP Filed Jan. 8, 1942 s Sheets-Sheet 2 KemeZb/Mflilk'.

April 18, 1944. I 2,346,859

' I POLISHED ROD CLAMP Filed Jan. 8. 1942 s Sheets-Sheet s @IWITITTIITJI Patented Apr. 18, 1944 POLISHED ROD CLAMP Kenneth N. Mills, 'l ulsa,pkla.,assi gnor to Bethlehem Steel Company, a corporati on of lennsylvania Appl cation Jansen 1 194.2, .fieriak e-szm 13 Claims.

My invention relates to gripping means for firmly holding suspended metalrods, and more particularly to -a hinged or book type polished rod clamp for use in connection withthe-pumping-of deep. oil wells.

In the usual method of pumping a petroleum well by a pump actuated :by astring of sucker rods, the so-called-polished rod is a short top-section of the string which is round andhighly polished in order to reciprocate through thestuffing box without causing undue wear thereto. The load of the well is transferred from the polished rod tothe beam hanger of the surface pumping unit by a gripping device-known as a polished rod clamp, which must be very rugged and strong, with a firm and positivegrip, yet with ,a minimum ofparts-and easy to install and remove.

A commonsource of accidents,; which itis necessary to avoid, is the construction of polished rod clamps with arms or other protuberances projecting from the body far enough to strike a passing workman while, the. well is being pumped.

As the polished rod clamp must carry theentire well load of severaltons without marring the. smooth surface of the polished rod, it-isa very difiicultpart to make. One of; the hardest problems to-overcome isthe slipping of the pol ished rod clampon the polished rod.

One object of my invention therefore, is to provide a strongandrugged clamping device.

A further object is a clamp which is simply constructed and easy to install.

Another object is a clampwhichiissafe and free from hazardous projections.

Still another object is a-clarnpwhichwillhold the polished rod firmly,..witho ut damage and without slipping.

Numerous other objects, purposes. and advantages of my invention will be apparent fro rnfthe following description, wherein-reference is made to the accompanying three sheets f drawings illustrating. the invention and wherein like numerals of reierence indicate like parts.

Figure l is-a-top plan view of the preferred form of .my polished. rodclamp showing 1 the insorted polished rod in operative position;

7 Fig.1 2 is a section taken .onthe line 2-2 .of 1, .butomitting the polishedrod to show more clearly the slanting superposed slotted prongs .fo-r

gripping the polished rod; 1 Fig. 3 is a side elevation of the clampwith the polished rod again inserted;

Fig. .4 .is asection taken ,on the line 4-.d, of Fig. .1. with the polished rod omitted;

. 5 is a section of .one ,of. the. halves of the.

mp-t n-. e. me se ti ias 2 sh ingin detail the-slotted prongs;

Fig. ;6 is a to .Plan view oja .rnodifieation of the clamp shown in Fig. :1 with a pivoted eye bolt andheadedco l ling pin;

' Fig. 8; and

Figs. 10 and llshow afurther. modification of the clamp shown in-Figd. with theslotted prongs madenormal tothe axis of the .polish e d rod,

Fig. 10 being atop. plan view andFig ll a section taken on the line I l--l-I of Fig. 10.

In the preferred form of my invention shown in'Figures 1' to 7,'. inclusive,'thebody of the polished rod .clamp consists ofit wo sectionso'r grips l andZ, of cast s teel or the like, hinged together onhingepin .3 with sufficientin'tervening space when closed. to .give afirm grip .on rods of different sizes, and providdtvith hollow substantially straight-walled interiorphamb'er 4'.

The clamping surface proper iof "each section of the body comprises va series of superposed. somewhat elastic steel prongs. 5 in said interior chamber 4,, which prongs .51 ar.e.directed at an upward angle'to the axis of the polishedl .rodffi whichfits into the central opening t me assembled clamp and areintegral' with. the sidewalls of their respective .body sections at their base ends. The-outer ends. of -the prongs 5 are machined to present a/smooth ,arc shaped'surfa'ce in contact with the polished rod 6, and the prongs themselves are relatively freetode flect and tighten their hold whentheynare' loaded. in .a plane parallel to theiaxis' .011 Said. polished rod.

[In Figures 1 to v inclusiveland in, Figures 10 and 11,the side edges oitheprongs ,5" arenot attached, to the body, of. the polished rod grip and permit consider,able.freedorififof' deflection. Where a more rigid structure is desired, however th t pe o ron s .LshQW i Fi res 8 and Q, circularly bored outof the solid block by a revolving cutting tool or the like lmay sometimes be preferred.

The angle of the prongs is not especially critical. Prongsj in Fi ures 1 ,to 7,.and .prongs 1 in Figures 8 and 9, are at angles about 15 from the horizontal, or about to the yertical axis of the polished "rod, butprongs of other inclinations, and eve horizo ta prongs. may be. used. pro s 8 in Figures '10 and IIffOrinstanQe. being. horint s hese. nlfi nes' 5. d must.

The individual sections I and 2, in Figures 1 to and 8 to 11, inclusive, are secured together by a bolt or bolts 9 each having a head It! and lock washer II and nut I2 thereon, whereas in Figures 6 and 7, each of said washers and nuts fastens on an eye bolt or eye bolts I3 connected to body half I with a second hinge pin I 4 and engaging a slot I5 in the other body section 2.

Hinge pins 3 and I4 may each be provided with a head of any conventional type, as for instance the round button heads I6 and I1 shown in Figures 6 and 7, or may be unheaded and drivefitted, as in the other figures. Elevated strengthening flanges or ribs I8 and boss I9 are refinements of design which may be regarded as optional features.

To install the clamp shown in Figures 1 to 5, inclusive, said clamp is placed about the polished rod 6 and the nuts I2 are screwed onto bolts 9, drawing the prongs 5 into contact with the polished rod 6. The other types shown are similarly installed. As the prongs: are located at a right angle or an acute angle to the axis of the polished rod, they will bend slightly when the grip is tightened up. This deflection will cause them to exert an uneven force on the polished rod, and the greater part of the force will be exerted on the lower side of the clamping surface. When a load is applied to the polished rod, it will tend to cause the prongs to deflect in the opposite direction to that caused by tightening the clamping bolts, and this contrary deflection will cause the prongs to exert an increased and balanced force on the polished rod. As the magnitude of this clamping force increases with the applied load, the polished rod clamp will not slip, and as the deflections of the prongs are small, it will not mark the polished rod to an unsatisfaotory'extent.

It will be noted that although the clamp is hinged to facilitate installation, none of the stress is carried on the hinge itself. All the stress is taken by the gripping prongs in the body of the clamp, and thereby a full length. positive grip is assured.

While I have shown and described my invention in considerable detail, I do not wish to be limited to the exact and specific details so shown and described, and I may use any or all such substitutions, modifications, or equivalents thereof, as are embraced within the scope of the invention, or are pointed out in the appended claims.

Having thus described my invention, what I claim as new and useful and desire to secure by Letters Patent is:

1. A rod suspending device comprising arcuate body sections hinged to admit a rod centrally therein, a plurality of separate resilient gripping members therein having smooth arcuate inner margins to hold the rod without substantially marring the same, bolts joining the body sections, and nuts threadedly engaging the bolts for tightening the body sections about the rod.

2. A rod clamp comprising a metal block formed of two sections, each having a side wall and having a central opening to receive a rod, yieldable integral gripping members having smooth inner faces in each section between the side wall and the rod to hold the rod, a hinge joining the two sections in the rear portion thereof, and bolts provided with nuts and extending through apertures in the vforward portion for bolting the sections together.

3. A rod clamp comprising a pair of rod gripping metallic members each having a side wall, a plurality of smooth arcuate contact surfaces integral with the side walls and adapted to grip on opposite sides of a rod, and clamping bolts for .connecting the pair of gripping members to gether.

4. A rod clamp comprising a metal block formed of two sections hinged together and having a central opening to receive a rod, opposing aligned horizontal slots cut in the walls of said opening forming integral annular prongs with smooth inner faces to permit a better grip on the rod, and transverse bolts for clamping th sections onto the rod.

5. A rod clamp comprisingarcuate metal body members hinged to admit a rod, inclined grooves positioned radially in said sections producing ribs having smooth arcuate inner margins to assist in gripping the rod, eye bolts hinged to one of the body members and engaging the other member, and nuts on the bolts for tightening the body members about the rod.

6. A rod clamp comprising arcuate hollow hinged members, smooth faced prongs therein normal to the vertical axis of a rod and contoured to receive and hold the rod without marring said rod, and transverse bolts provided with nuts for tightening the prongs about the rod.

7. A rod clamp comprising arcuate hollow hinged members, a plurality of superposed flat slanting prongs having smooth arcuate inner margins to grip a rod therein without substantially marring the same, eye bolts pivoted to one of the hinged members and passed through the other member, and nuts threaded onto the eye bolts for tightening the prongs about the rod. 8. A rod clamp comprising arcuate hollow hinged members, a plurality of integral resilient prongs having smooth arcuate inner faces for gripping a rod firmly therein, said prongs being inclined at an angle to the vertical axis of the rod, eye bolts pivoted to one hinged member and passed through the other member, and nuts threaded onto said eye bolts for tighteningthe hold of the prongs on the rod.

9. A rod clamp comprising arcuate metal body members hinged to admit a rod, integral smoothfaced arcuate clamping prongs therein to hold the rod in a fixed position, and transverse bolts provided with nuts for tightening the clamping jaws onto the rod.

10. A polished rod clamp comprising a pair of arcuate hinged metallic half members, a plurality of fitted gripping prongs having smooth arcuate inner margins inside each half member integral therewith and inclined'upwardly toward the vertical axis of a polished rod to resist and support the load thereof, and transverse bolts for nuts for tightening the grip of the teeth on said 10 polished rod.

13. A polished rod clamp comprising a block formed of two hinged metallic body members and having a central opening adapted to receive a polished rod, a set of individual arcuate prong members in each body member adapted to grip and hold said polished rod, and transverse bolts for bolting the body members together to clamp said prong members against the polished rod.

KENNETH N. MILLS. 

